Pack Year Calculator

Summary

Calculate your smoking history in pack-years (packs per day × years smoked) for clinical lung cancer risk assessment.

How it works

1. Enter the average number of cigarettes you smoke (or smoked) per day.
2. Enter the total number of years you have smoked.
3. The calculator divides cigarettes per day by 20 to get packs per day.
4. Packs per day is multiplied by years smoked to produce the pack-year total.
5. A risk summary based on common clinical thresholds is displayed.
6. Use the result in conversations with your healthcare provider.

Use cases

• Determine eligibility for annual low-dose CT lung cancer screening.
• Document smoking history for surgical pre-assessment.
• Stratify COPD and cardiovascular risk in primary care.
• Support pulmonology referrals requiring a quantified smoking history.
• Patient education — visualize cumulative tobacco exposure.
• Research and clinical trial enrollment screening.

Frequently Asked Questions